The effect of high-voltage waveforms on ESP current density distributions

The efficiency of an electrostatic precipitator (ESP) collecting high resistivity dust is degraded by maldistribution of corona current in the interelectrode space. The current distribution can be improved by applying novel high-voltage waveforms to the discharge electrodes. Online measurements are presented of collecting plate current density distributions in a precipitator collecting fly ash from a coal-fired electric generating plant. The precipitator was operated with both round-wire and barbed-strip discharge electrodes. The current density distributions are compared for three high-voltage waveforms: conventional, pulse, and intermittent energization. A direct relationship is established between the ability of the waveforms to distribute useful values of corona current and the collection efficiency of the ESP